Conventional iron-type golf club heads often utilize a perimeter-weighting element to improve the mass properties of the head. Perimeter-weighted irons are typically more “forgiving” than those of the blade type because the elevated moment of inertia generally associated with perimeter-weighted designs reduces undesirable head rotation when a ball is mishit, or struck away from the point of orthogonal projection of the club head's center of gravity onto the striking surface of the head. Diminished rotation of the club head at ball impact beneficially affects the accuracy and distance of mishit shots.
Other known improvements associated with iron-type clubs include, e.g., replacing portions of the metallic material of the club head with lower-density non-metallic inserts.
The resulting discretionary-weight surplus may be strategically distributed throughout the club head to increase its moment of inertia. However, conventional inserts are commonly made from substantially inelastic materials to comply with USGA rules that require all parts of the golf club to be rigid. Such inserts generally lack the compliance necessary to augment forgiveness of the club head on off-center shots. Moreover, typical inserts composed of more compliant material generally have a monolithic construction antonymous with superlative head-weight distribution.